Vinyl resins plasticized with formals of tetrahydrofurfuryl alcohol



United States Patent 3,328,334 VINYL RESINS PLASTICIZED WITH FORMALS 0F TETRAHYDROFURFURYL ALCOHOL Charles H. Fuchsman, Cleveland Heights, Ohio, assignor to Ferro Corporation, Cleveland, Ohio, a corporation of Ohio No Drawing. Filed May 14, 1964, Ser. No. 367,539 Claims. (Cl. 260-30.4)

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materials to the resin composition results in better or increased physical properties and a faster solvation of the resin than is obtained with a conventional plasticizer alone.

Accordingly, a primary object of this invention is to 3 provide an improved and novel composition of matter which exhibits an improved plasticizing effect on halogen containing polyvinyl resins.

A further object of this invention an improved and novel composition of matter having a plasticizing system composed of a conventional plasticizer and a lesser amount of an acetal prepared from an oxygen containing ring compound.

Another object is to provide an improved and novel composition having a plasticizing system composed of a conventional plasticizer and bis(tetrahydrofurfuryl) formal.

Other objects will become apparent as the description proceeds.

The present inventor has discovered that when between 1 and parts per hundred parts of resin of an acetal of an oxygen containing ring compound, preferably bis (tetrahydrofurfuryl) formal, have been incorporated into vinyl halide polymers in the presence of a larger quantity of a plasticizer (e.g. from 25 to 49 parts per hundred parts of resin) of the kind discussed below, the resultant plasticized vinyl halide composition has in general enhanced strength, enhanced elongation and faster resin solvation characteristics. The mechanism by which the above characteristics are obtained would seem to involve synergism between the plasticizer and the acetal compound, although I dont wish to be bound by this theory.

Thus, briefly stated the invention involves a composition of matter comprising a halogenated vinyl resin, a plasticizer and an acetal compound to be later described in detail which is responsible for the increased benefits of the plasticizer system.

The term halogenated vinyl resins includes vinyl halide homopolymers, vinyl halide co-polymers with vinyl acetate and vinyl halide co-polymers with vinylidene halides. It also includes post-halogenated polyvinyl polymers. Various mixtures of the resins may be resorted to according to the individual desires or to meet the necessary physical requirements. The halide utilized is preferably the chloride although the fluoride or bromide may also be employed, and as used throughout this specification and claims, the term halide shall include, but be limited to, these three halogens.

The plasticizers employed within the scope of this invention are esters obtainable from alcohols containing 1 to 4 hydroxyl groups and acids containing 1 to 3 acidic hydrogen atoms. These esters are normally liquid at room temperature and have a boiling point at atmospheric pressure not below 300 F. Examples of the above compounds are di(2-ethylhexyl) phthalate, diisodecyl phthalate, di (tetrahydrofurfuryl) phthalate, di(2-ethylhexyl) azelate,

10 di(2-ethylhexyl) sebacate, pentaerythritol tetracaprate, butyl benzyl phthalate, di(isooctyl) phthalate, epoxidized soya bean oil and tricresyl phosphate. It will be understood that this list is only illustrative and that other plasticizers may also be employed if desired.

0 Referring to the acetal compound used in this invention, it should be noted that the said acetal is prepared from oxygen containing ring compounds. Although various acetals are operative in this invention, the preferred compound is bis(tetrahydrofurfuryl) formal. These compounds all have the general formula:

OX2 L L where n is an integer from 1 to 2, Y, is an integer from 0 to 4, R an alkylidene group of 1 to 8 carbon atoms and X is selected from a member of the group consisting of hydrogen and alkyl radical. 0 The above compound may be obtained by mixing an oxygen containing ring compound such as tetrahydrofurfuryl alcohol or tetrahydropyran-Z-methanol with paraldehyde (an acetaldehyde trirner), formaldehyde or methylene chloride and reacting the same to produce an acetal or formal of tetrahydrofurfuryl alcohol, Where methylene chloride is used instead of formaldehyde, a suitable base must be used to neutralize the resulting hydrogen chloride. These compounds have very strong solvency for a resin such as polyvinyl chloride and copolymers of vinyl chloride and other vinyl polymers and in addition to the strong solvent power have a relatively high boiling point. This combination of properties is unexpected inasmuch as usually only the very low boiling point solvents have a y strong solvating power for polyvinyl chloride resins and, usually the higher the boiling point, the lower the solvent power. The compounds are unusual also in that the chemical structural unit COC-OC which characterizes acetals is quite unusual among industrially significant solvents. The strong solvent properties of these compounds are believed to be related to this structure.

As stated previously, the preferred compound employed in this invention is bis(tetrahydrofurfuryl) formal (BTFF), and reference is directed to Patents 2,153,134 and 3,072,607, which are of particular interest relative to this compound and to other related acetals. In the preferred method of making this specific compound approximately 2 to 2% equivalent weights of tetrahydrofurfuryl alcohol are reacted in an acidic solution with about 1 equivalent weight of formaldehyde to provide the additional plasticizing compound utilized in the present invention. The tetrahydrofurfuryl alcohol, which is the preferred oxygen containing ring compound starting material, can be reacted Wit-h another aldehyde in place of the previously described formaldehyde to produce an acetal of tetrahydroufrfuryl alcohol in which two adjacent tetrahydrofurfuryl alcohol rings are always spaced by the grouping where R is an alkyl group of 1 to 6 and preferably 1 to by a die, aged 24 hours at room conditions and tested for 3 carbon atoms. tensile strength (p.s.i.), percent elongation and hardness While BTFF is the preferred compound that is utilized (Shore A). The plasticizing system for this and the folin the present composition, other acetals may also be lowing several examples involve a conventional phthalate used, bis(tetrahydropyran-Z-methyl) formal is one of plasticizer and bis(tetrahydrofurfuryl) formal (BT'FF) these and is prepared by mixing substantially 3 moles of varied as to the amount of each of the foregoing comtetrahydropyran-Z-methanol and 15 moles of 91% paraponents and the following comparative results were noted:

formaldehyde and 4.0 ml. of 38% HCl and 50 grams of toluene. The mixture is heated for a few hours and then t 1 B FF H d m Tensi e t Ell RGSS Oil 2.- the water is removed by a zeotrop 1c d1st1llatron. Th1s mlx- 10 fig g (phn) (Show A) g Strength ture is then neutralized with sodium carbonate and then (phr.) (percent) (13.5.1.) vacuum filtered. The filtrate is distilled to obtain the desired compound.

Another desirable compound employed in the composri8 8 2g 2% 2,760 tion of this invention is the diformal of tetrahydrofurfur- 3 2g 3g fig yl alcohol and 2,5 dimethyl tetrahydrofuran having the formula Hz? (EH2 HzC-OHZ H2C--CH3 H2O HoCHi0CHZ0CHtcH HocHtocHt-ooH2CH CH2 This compound is prepared by mixing an approximate 'It will be seen that the inclusion of BTFF in the com- 9:1 molar ratio of tetrahydrofurfuryl alcohol and 2,5 position as set forth above resulted in a significant imbis(hydroxymethyl) tetrahydrofuran about 2.2 moles of provement in the percent elongation up to level wherein formaldehyde and HCl is added as a catalyst. Toluene is 50 percent of the phthalate plasticizer is substituted by also added to remove the water azeotropica-lly. The result- B'PFF. The tensile strength improved considerably when ing mixture contains about 1 part of the diformal of the BTFF replaced about 20 percent of the original tetrahydrofurfuryl alcohol and 2,5 dimethylol tetrahyphthalate plasticizer. The hardness did not significantly drofuran and about 3 parts of bis(tetrahydrofurfuryl) change at any level of the plasticizer and BTFF relaformal. tionship.

Similarly the tetrahydrofurfuryl-terminated polyformal The elongation test in this and the following example of 2,5 dimethylol tetrahydrofuran having the formula was run by preparing samples about 65 mils thick of a H2C-CH2 H2O CH2 H2CCHg 1110 Ho- CHZ OCHZOCHZ CH Ho OHi0OHi0CHt( 3H CH2 O O n 0 where n is an integer of from 1 to 4 is prepared by using standard dumbbell shape, and subjecting them to linearly an approximate l to 1 ratio of tetrahydrofurfuryl alcohol increasing tension until they break. The increase in length and 2,5 bis(hydroxymethyl) te'trahydrofuran, HCl is of the specimen, which is solidly confined to the narrow added as a catalyst and toluene is added to azeotropically neck of the sample is noted as follows: The length of remove the water. Here the resulting mixture of termithe neck at failure, divided by the length of the neck nated polyformals would be expected, on statistical in the original unstressed sample, and the quotient thus grounds, to contain a significant proportion of 3,5 and 6 obtained multiplied by 100, gives the percent elongaring compo nds in addition to the th oreti l 4 r ng r tion. The tensile strength is the force exerted at failure ture. divided by the original cross sectional area of the neck.

The plasticizing system involved in this invention com- E l H prising the above mentioned plasticizers and an acetal xamp may be incorporated into the vinyl resin by a variety The same procedure was followed as in Example I, usof methods. It can be added to the resin utilizing hot rolls ing diisodecy'l phthalate as the plasticizer. or other machines employed to mix resins. The important The following results were obtained. requisite is that resin and the plasticizing system be completely dispersed one within the other.

The invention will be further illustrated by the following examples showing results which are consistent with the theory set forth earlier of a synergistic effect of (percent) (p.s.1.)

various acetals and the plasticizer. 50 0 92 44s 2, 510

For the following examples the basic composition be- 35 l2 3? fig 51x 8 low is used: 0 so 83 375 1,430

Example I Standard compositions of 100 parts of polyvinyl chlo- Optimum results were obtained in percent elongation ride resin, 50 parts per hundred parts of resin of a plasand tensile strength when about 20 percent of the plasticizing system, 2.5 parts per hundred parts of resin of a ticiZer was replaced by an equivalent amount of B'I'FF. barium-cadmium stabilizer and 0.25 part per hundred H d e a ot significantly afiected parts of resin of stearic acid were mixed or milled for 10 E l I minutes at 330 F., pressed at 350 F. for 3 minutes at xamp 6 32,000 pounds pressure to form plaques having a thick- The same procedure was followed as in Example I, using ness of substantially mils, cut into dumbbell shapes di(tetrahydrofurfuryl)phthalate as the plasticizer.

The following results were obtained.

Di(tetrahydro- Elonga- Tensile rfuryl) B TFF Hardness tion Strength phthalate (phr.) (Shore A) (percent) (p.s.i.)

Here optimum results were also obtained in elongation and tensile strength when about percent of the plasticizer was replaced by an equivalent amount of BTFF. There is a considerable loss in these properties when the BTFF content exceeds the optimum. Hardness is reduced when the BTFF replaces substantially 50 percent or more of this plasticizer.

Example IV The same procedure was followed as in Example I. However, here and in the following example, the primary plasticizer involved was based on alkyl esters of straight chain dicarboxylic acids.

The same procedure was followed as in Example IV, using di(2-ethylhexyl)azelate as the plasticizer.

Di(2-ethyl- BTFF Hardness Elongation Tensile hexyl) azelate (phr.) (Shore A) (percent) Strength (phr.) (p.s.1.)

Similar results were obtained as in Example IV, that is best and highly improved results occurred when 20 percent of the plasticizer were replaced with BTFF.

Example VI The same procedure was followed as in Example I. However, here and in the following example, the plasticizer involved was based on esters of monocarboxylic acids with polyhydric alcohols.

Pentaerythritol BTFF Hardness Elongation Tensile tetracaprate (phr.) (Shore A) (percent) Strength (phr.) (p.s.1.)

Best results were obtained with a 20 percent replacement of plasticizer with BTFF. A higher proportion of BTFF causes a material loss in elongation and strength properties.

Example VII The same procedure was followed as in Example VI, using epoxidized soya bean oil as the plasticizer.

Epoxidized BTFF Hardness Elrm atinn Tensile soya bean oil (phr.) (Shore A) (percent) Strength (phr.) (psi.

Again optimum results were obtained when substantially 20 percent of the plasticizer was replaced with BTFF.

Example VIII The same procedure was followed as in Example VI, using tricesyl phosphate as the plasticizer.

Tricrcsyl BTFF Hardness Elonga- Tensile phosphate (phr.) (Shore A) tion Strength (phr.) (percent) (p.s.i.)

Optimum elongation test results were obtained when 20 percent of the tricesylphosphate was replaced with BTFF.

Example IX Here the same procedure for formulating the composition was followed as in Example I including the use of dioctyl phthalate (DOP). However the resin involved comprised a vinyl chloride-vinyl acetate copolymer in which the proportion of vinyl acetate therein is substantially 13 percent.

Dioctyl BTFF Hardness Elonga- Tensile phthalate (phr.) (Shore A) tion Strength (phr.) (percent) (p.s.i.)

Using this copolymer a considerable increase in elongation properties occurred when substantially 25 percent of the plasticizer was replaced with BTFF. The tensile strength herein, however, was reduced.

Example X The same procedure was followed as in Example IX including the same plasticizer DOP. However, the vinyl acetate proportion in the vinyl chloride-vinyl acetate resin was substantially 5 percent.

Dioctyl BTFF Hardness Elonga- Tensile phthalate (phr.) (Shore A) tion Strength (phr.) (percent) (p.s.i.)

Best results occurred when substantially 25 percent of the dioctyl phthalate plasticizer was replaced with BTFF. The strength was considerably increased at this proportion of primary plasticizer and BTFF. However, at substantially 50% replacement of the dioctyl phthalate with BTFF, increased results were also obtained in both elongation and strength properties.

Example XI Here the same procedure was followed as in Example 1X also using dioctyl phthalate. The resin used in the composition was, however, a vinyl chloride-vinylidene dichloride copolymer in which the vinylidene chloride was 7 subst atnially 10 percent.

Best results were also found when substantially 25 percent of the plasticizer was replaced with BTFF. An increased elongation occurred at this proportion of the plasticizer and BTFF.

Example XII In this example, the same compositions were employed in the manner set forth in prior Example I. However, the plasticizing system utilized a conventional dioctyl phth alate plasticizer and about a 13% mixture of the diformal of tetrahydrofurfuryl alcohol and 2, dimethylol tetrahydrofuran and bis(tetrahydrofurfuryl) formal.

Dioctyl Diiorrnal Hardness Elonga- Tensile phthaiate mixture (Shore A) tion Strength (phr.) (phr.) (percent) (p.s.i.)

The inclusion of the diformal mixture in the composition resulted in considerable improvement of the tensile strength. At increasing formal content, the hardness is decreased, showing the eflect of increased efliciency of plasticization.

Example XII] Dioctyl BTFF Hardness Elongation Tensile phthalate (phr.) (Shore A) (percent) Strength (phr.) (p.s.i.)

Here an increased elongation and tensile strength occurred up to a substitution of 50 percent of the plasticizer by the terminated polyformal. Hardness decreased with increasing formal content, again showing the effect of improved plasticization.

Example XIV As in Example XIII, the Same procedure and ingredients were utilized as the previous examples. The plasticizer used is dioctyl phthalate and the BTFF homolog is bis(tetrahydropyran-Z-methyl) formal.

Dioctyl Bis(tetrahydro- Hardness Elonga- Tensile phthalate pyran-Q-methyl (Shore A) (Percent) Strength (phr.) ionnal (phr.) (p.s.i.)

Here we note that a definite increase in tensile strength occurs at all levels of plasticizer and formal substitution thereof.

The plasticizers of this invention are employed in varying amounts but they normally are present from about 25 to 49 parts per hundred parts of resin. The acetals used in conjunction with the plasticizers are present in amounts from about 1 to 25 parts per hundred parts of resin.

Thus, it can be seen from the foregoing examples that the incorporation of a plasticizing system comprising a plasticizer as discussed above and an acetal, preferably bis(tetrahydrofurfuryl) formal to a halide containing vinyl resin causes improvements in the physical characteristics of the said resin over those achieved when a conventional plasticizer alone is used. It would appear that the strength and elongation properties are the ones most commonly affected.

Having thus described my invention, what I claim is:

1. A composition of matter comprising a major portion of a mixture of a vinyl resin selected from the group consisting of vinyl halide homopolymers, vinylidene halide homopolymers, copolymers of a vinyl halide and a vinylidene halide, copolymers of a vinyl halide and vinylacetate and copolymers of a vinylidene halide and vinylacetate, a stabilizer and from 1 to 50 parts by weight per parts by weight of resin, of a plasticizer, said plasticizer being an acetal having the general formula:

X is selected from the group consisting of hydrogen. and an alkyl radical having less than 4 carbon atoms.

2. The composition according to claim 1 wherein said 1 acetal is bis(tetrahydrofurfuryl) formal.

3. The composition according to claim 1 wherein1 R is CH 4. The composition according to claim 1 wherein said acetal is the diformal of tetrahydrofurfuryl alcohol and t 2,5 dimethylol tetrahydrofuran.

5. The composition according to claim 1 wherein said acetal is a mixture of bis(tetrahydrofurfuryl) formal with a member selected from the group consisting of bis(tetr=ahydropyran-Z-methyl) formal and the diformal of tetrahydrofurfuryl alcohol and 2,5 dimethylol tetrahydrofuran.

6. A composition of matter comprising a major portion of a mixture of a vinyl resin selected from the group consisting of vinyl halide homopolymers, vinylidene halide homopolymers, copolymers of a vinyl halide and a vinyl idene halide, copolymers of a vinyl halide and vinylacetate and copolymers of a vinylidene halide and vinylacetate, about 1 to 5 parts by weight of stabilizer per 100 parts by weight of resin, about 25 to 49 parts per hundred parts of resin of a first plasticizer, said first plasticizer being an ester derived from an alcohol containing one to four hydroxyl groups and an acid containing 1 to 3 acidic hydrogen atoms, and about 1 to 25 parts per hundred parts of resin of a second plasticizer, said second plasticizer being an acetal having the general formula:

wherein n is an integer from 1 to 2, Y is an integer from 0 to 4, R an alkylidene group of 1 to 8 carbon atoms and X is selected from the group consisting of hydrogen and an alkyl radical having less than 4 carbon atoms.

7. The composition according to claim 6 wherein said acetal is bis(tetrahydrofurfuryl) formal.

8. The composition according to claim 6 wherein said acetal is bis(tetrahydropyran-Z-methyl) formal.

9. The composition according to claim 6 wherein R is CH2.

10. The composition according to claim 6 wherein said acetal is a mixture of bis(tetrahydrofurfuryl) formal with a member selected from the group consisting of his (tetrahydropyran-2-methy1) formal and the diformal of tetnahydrofurfuryl alcohol and 2,5 dimethylol tetrahydrofuran.

References Cited UNITED STATES PATENTS 2,153,134 4/1939 Dickey et a1 260347.8 2,993,915 7/1961 Luskin 260347.8 3,072,607 l/1963 Fisch et a1. 260347.8

10 MORRIS LIEBMAN, Primary Examiner.

L. T. JACOBS, Assistant Examiner. 

1. A COMPOSITION OF MATTER COMPRISING A MAJOR PORTION OF A MIXTURE OF A VINYL RESIN SELECTED FROM THE GROUP CONSISTING OF VINYL HALIDE HOMOPOLYMERS, VINYLIDENE HALIDE HOMOPOLYMERS, COPOLYMERS OF A VINYL HALIDE AND A VINYLIDENE HALIDE, COPOLYMERS OF A VINYL HALIDE AND VINYLACETATE AND COPOLYMERS OF A VINYLIDENE HALIDE AND VINYLACETATE, A STABILIZER AND FROM 1 TO 50 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF RESIN, OF A PLASTICIZER,SAID PLASTICIZER BEIENG AN ACETAL HAVING THE GENERAL FORMULA: 